I would execute your plan in a heartbeat. While an extra bath might make a difference in a home when the baths increase from one to two, or possibly two to three, it sounds like you have wasted space. Personally, I always prefer larger laundry rooms and kitchens, as that's where you are really doing housework/cooking and having extra space for convenience and supplies is wonderful.

Also, who wants to clean the extra toilet? There can be too many bathrooms (ask me how I know).

Can you close up that door and make the entry into a different room in the house.
I’d be hesitant to rid of it completely.

With what you have described, I would vote for your plan in a heartbeat! I’d never get rid of a powder room on the main level, but an additional toilet besides the powder room??? Yeah, I’d be all about better function for both the laundry room and a pantry. I also think, that if resale is a concern, that would be a much better resale point than some weird extra bathroom in a house that already has a very comfortable ratio of bathrooms. Most people go Gaga over an ample laundry room and nice walk in pantry. And as someone who raised a decently large family, your plan seems ideal to me in multiple stages of life. (Young children, older children, and now empty nest.)

Is there any room on the first floor that could ever be a bedroom? Would that bathroom with a shower ever be used by a family member with limited mobility who needs to sleep on the first floor and needs a full bathroom too? If you can't imagine any scenario in which that is possible, then I agree with your plan to remove the full first floor bath and keep a powder room.

To Kendrah's point ^^ -- think about future potential need/use. Could the door be moved for the full bath so it doesn't open into the Kitchen? Could you then convert the Half-Bath to the Laundry Room?

Just think about it b/f you decide.

(With no layout provided, it's difficult to tell what is/is not possible.)